And rudolph e



Dec. 2, 1924. 1,517,401

F. s. .cALnERwooD .E'r AL STOPPING MECHANISH /N VEN TOPS Dec.' 2,v 1924.- 1,517,401'

. F. s. vcALDERwoorz ET AL sToPPING MECHANISM Filed Aul. 26 1922 2 Sheets-Sheet 2 lll Patented Dec. 2, 1924.

UNITED STATES PATENT OFFICE.

FREDERIC S. CALDERWOOD, OF RIVER-TON, NEW JERSEY, AND RUDOLPH E. ZERU- NEITH, 0F PHILADELPHIA, PENNSYLVANIA, ASSIGNORS TO VICTOR TALKING MACHINE COMPANY, A CORPORATION OF NEW JERSEY.

STOPPING MECHANISM.

Application filed August 26, 1922. Serial No. 584,405.

To @ZZ 'mimi/2y it l'may concern.:

Be it known that we, FREDERIC S. CALDER- wcoo, a citizen of the United States, and a resident of Riverton, in the county of Burlington, State of New Jersey, and lftcoonrn E. ZnnUNnrrH, a citizen of the United States, and a resident of the city of Philadelphia, in the county of Philadelphia and .State of Pennsylvania, have invented certain new and useful Improvements in Stopping hlechanisms, of which the following is a specification.

Our invention relates to stopping mechanisms and more particularly to those devices by the operation of which a talking machine mechanism is stopped either mannail)v or automatically, or manually and automatically at such times or places as it may be found desirable so to do.

ln those talking machines wherein a spring motor is employed to rotate the turn table the stopping of the machine is usually effected by manually or automatically applying' a brake to the periphery of the turntable or to a flange depending therefrom, or to any other appropriate part of the motor. There are, however, other talking machines in which the. electric motor, mounted directly on the turntable spindle or geared thereto, is used to rotate the turntable, and in those machines the mere application of a brake to the turntable o-r to the motor to stop the further operation thereof would injure, or tend to injure, the electric motor. ln such machines, 'therefore, the usual way of stopping the rotation of the turntable is to cut otli the electric current to the electric motor by opening an electric switch in the motor current.

Our invention is arranged and adapted to perform either or both of these functions, and the term stopping mechanism as employed herein refers to a mechanism operative to apply a brake to some partof the machine to stop the continued rotation thereof, or to break an electric current, by which the driving motor is driven; and the term stop member as employed by us herein applies to that member which, when released or otherwise moved, either automatically or manually, is connected to and moves a brake against some moving' part of the talking machine to stop the rotation of the motor, or moves an electric switch in such a manner as to break the circuit which includes an electric motor, operative to drive the machine.

l e have therefore shown and described two forms or embodiments of our invention, one operating as a switch throwing mechanism and the other operating as a brake mechanism.

The objects of our invention are to provide a stopping` mechanism, of the character above indicated, which .may be easily and accurately set to operate automatically at an exact predetermined point, preferably at or near the end of the sound record groove; to provide a stopping mechanism which is delicate, and which is actuated upon the application of a relatively light pressure; to provide a structure wherein the releasing parts of the stopping mechanism are subjected to substantially no wear, so that the release of the stop member, at exactly the desired point, is readily accomplished, and so that there is no Wear on the setting or resetting mechanism tendingto vary the time when the device will operate to stop the machine.

Fnrthcr objects of our invention are to provide a structurel wherein the stop member may be released by hand without jamA ming or wearing the surfaces which cooperate to effect the automatic operation of the device and whereby the means .for mauually releasing the stopping member may" be operated in the reverse direction to reset the device; to provide a handle, for maunally operating the stop mechanism and for resetting the same, which is provided with an abutment which engages the detent of an automatic releasing mechanism so that said abutment is readily moved by the handle in one direction out of engagement with said detent to actnate the stopping mechanism and whereby said abutment is moved in the opposite direction by said handle to bring said abutment into engagement with the end of said detent.

Other objects of our invention will appear in the specification and claims below.

In the drawings forming a part of this specification and in which the same reference characters are employed throughout the various views to designate the same parts,

Fig. l is a plan view of one embodiment of our invention, the device being one in which the stopping of the talking machine is effected by a breaking of an electric current supplied to the motor (not shown) for turning the turntable spindle; Fig. 2 is a side elevational view of the structure shown in Fig. 1, the motor board on which the automatic stopping mechanism is mounted and the electric switch being shown in ver-A tical cross-section; and Fig. 3 is a vertical sectional view of the frictional connection between'the detent andthe adjustable arm.

Fig. L1 la further detail of construction, showing the coacting surfaces of the detent and abutment member, and theparts slightly separated.

Fig. is a plan View of a niodified'form of our device wherein the stopliiing of the talking machine is elected by the application of av friction brake to the 'flange of the turntable; and Fig. 6 is aside elevational View of the structure shown in Fig. 5, certain parts thereof being shown in vertical crosssection.

Referring first tothe embodiment of our invention shown in Figs. 1 to a, themotor board 1 is suitably provided with a hole or opening 2 throughwhich upwardly passes a. turntable spindle 3, on the upper end of which is carried a turntable 4 having downwardly depending peripheral flange 5 and a top frictional surface 6,"preferably of felt or similarinaterial. lt is upon this friction surface 6 thatrthe record 7 lies asit is being rotatedl by the turntable under the 'reproduc'er orsound box (not shown). The base plate 8 may be of any suitable shape. It preferably stamped from flat sheet 'metal It is preferably providedwith` suitable holes 9 through which screwsmay be passed for the purpose of rigidly securing it to the top of the motor board 1.

`From the underside of the base plate 8 depends a' vsmall electric switch 10, the casing 10 of which is rigidly secured tothe base plate 8. `This electric switch 10 may be and preferably is of any1 appropriate construction and preferably comprises a pair of oppositely extending metallic switch lingers 11-11claniped betweenv a, top plate l2 and a bottom plate 13 but insulated therefrom by insulators 1 l --14. The ltop'und way the fingers 1L-11 are completely insu*- lated from the vpivot pin 15 and from the metal base plate 8. In Fig. 2 the switch is shown as closed; that is to say, as completing the 'electric circuit to the motor. ln this position, the oppositely extending switch lingers 11-w11 engage stationary contacts 19. -rigidly secured to the bottom of the casing 10 and having extensions 19w--20 extending through the casing for attachment to the electric leads or wires 21 and 22. The casing 10 is of'insulating material and the extensions 19-20"may be permanentlyiinbedded therein. Whenthe switch member (comprisingthe fingers 11, the toppl-ate 12, the bottom plate 13, land the insulators 111) is turned on its pivotv pin 15 through a relatively small angle, the switch fingers 11-11 move out of engagement with the stationary contacts 19, 2() thereby breaking the electric circuit to the driving motor .(not shown)4 The topplate 12 is provided with an arm 23 extending upwardly through an arcshaped slot 24 in the base plate 8 and the top end of said arm 23 loosely tits in a suitable opening 25 in the stop member 2G. A. switch of this type is described and shown in the U. S. patent to Murray, No. 1,229,642. patented June 12, 1917.

The stop member 26 is pivotally mounted on the base plate 8 on a pivot pin or stud 27, and mounted upon and carried by said stop member is an abutment member 28. In the embodiment of our invention as shown in'Figs.' 1 to 3, thisabutment member isi-mounted upona. pivot pin 29 tightly cured to the stop member 26. To said abut` ment member is rigidly connected Vthe handle 30.

Mounted to oscillate about the axis of a stud 31, stationarily mounted on the base plate 8, is adetent 32 extending from said pivot or stud 31 toward said abutment member 2S. This detent 32 isy arranged to have but slight Aangular movement about the axis of the stud 31, said angular movementbeing limited by the upper stop pin 33 on the one side, and the lower stop pin 34 on the other side. Also mounted to oscillate about the axis of the stud 81 is a radially extendingy arm 85 terminating in a bifurcated end forming two lingers 36 and 37. The linner side of one finger (36) is arranged to be engaged and actuated by the lower end of al vertical stud 3S which is rigidly secured at its upperend to the under side ofi a swinging tone arm -(fnot shown), while the `other finger 3T is preferably provided with `an upwardly extendin g handle 39 for the convenient manualoperationor' adjustment of the arm 35. The bifurcated arm and the detent 32 are preferably'directlyfmounted on a sleevev 40 which is freely rotatableon the stud 31. Said rotatable sleeve 40 provided with a flangf,l

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40"V slightly spaced from and out of contact with the base plate 8 by a washer 40". Between the arm 35 and the flange 40n and between said detent 32 and the adjustable arm 85 are friction washers 4l. The detent the adjustable arm 35 and the friction wash-- ers 4l are all yieldingly held pressed together on the sleeve 4() b y a spring washer 42 having a radial slot 42a therein, the sides of which fit `with a circumferential groore or slot 40C in the sleeve 40.

By reason of the construction the detent the adjustable arm the sleeve 40, friction washers Atl-4l and spring washer 42 all freely move together as one piece on the stud 3l., within the limits of the oscillation of the detent 32 (the oscillating move-- nientof the detent 252 being' limited by the step pins 33 and 84). but by overcoming the frictional resistance between the washers 4l and the parts engaged thereby, the arm 3f may be readily angularly adjusted with respect to the detent 32 for the purpose of setting the finger 36 in the proper position for engagement by the stud S8 at the end of the reproduction of sound from a particular record. A detent, an adjustable bifurcated arm with the frictional washers therebetween and the relation thereof to a pin depending from the tone arm are also clearlv shown and described in the said lil. S. Patent No. 1,229,642, and a further description of the construction thereof herein is not deemed necessary for an understanding of the present invention. The detent 32 is preferably provided with an upwardly extending rigid stud 48 and the stop memi ber 26 is also preferably provided with a similar upturned rigid stud or pin 44 and to the ends of said studs or pins 43, 44 are preferably respectively attached the opposite ends of a coil spring 45.

The abutment member 28 preferably com.- prises an arm, projection or abutment 46 extending substantially away from the axis of the pivot pin 29 and substantially toward the axis of the stud 3l upon which the detent 32 pivoted. The end of the arm or projection 46 is preferably provided with a transverse flat surface 47 normal to a line drawn thereto from the axis of the pivot pin. with a sharp corner or edge 48, and a curved arc-shaped upper surface 49 substantially concentric with the axis of tht` pin 27 around which the stop member 2G nieves. The end of the detent 32 is also preferably provided with a transverse flat surface 50 which, when the parts are in the position shown in Fig. l, squarely fits against the flat surface- 47 of the arm or abutment 46. The detent 32 is also preferably provided with a sharp edge or corner 5l at vthe lower end or side of the said flat surface :30. These surfaces are more clearly indicated in Fig. 4.

The position of the studs 48 and 44 is such that when the device is set in the nonstopping position shown in Fig. l) the tension of the spring` 45 will lightly hold the detent 32 against the lower stop pin $34.

'lhe manner in which the coacting surfaces of the detent 32 and abutment member 28 cooperate in the operation of the device `will be fully explained below.

The stop member 26 is also preferably provided with an upwardly projecting rigid stud 52 which serves as a stop to limit the rotational movement of the abutment member 28 and its handle B0 in a clockwise direction with respect to the stop member 2G.

rl`he base 'plate 8 is preferably also provided with two upwardly extending stoppins or studs 53 and 54 which serve to limit the movement of the handle or lever 30 and hence of the stop member 26 beyond a predetermined point in either direction.

The operation of the device.` so far as has been above described, is as follows:

Assuming the adjust-able arm to have been so set with respect to the detent 32 that when the pin 38 carried by the tone arm engages the finger 8G of the arm 35 the reproducer will be at the end of the reproduction of sound of a particular record on the turntable, that the lever 30 has been swi'ing to the on position (herein referred to as the non-stopping position) shown in Fig. l, and that the flat surface 47 on abutment member 28 is held against the flat surface 50 of the tetent 32 by the tension of the spring and assuming further that when the parts are in this position, the switch fingers 1l, 1l are in engagement with the stationary contacts 19. 20, thus closing the circuit through the wires 2l and 22 to the electric motor by means of which the spindle -l is rotated, the parts will, thereafter normally remain in this position until the pin 38 engages the arm 8G as the tone arm swings over the record during the reproduction of sound therefrom. Yhen the piu 38 engages the finger or arm 8G it will swing the arm 35, and with it the dete-nt 32, in an anticlockwise direc-tion around the pivot 3l, thus transversely sliding the flat surface 50 of the detent over the flat surface 47 of the arm or abutment 28 until the sharp corner or edge 5l reaches the sharp corner or edge 48 of the forwardly projecting arm 46. During this part of its movement the small y flat surface 50 of the detent 82 merely slides transversely over the small fiat surface 47 of the abutment without forcing the abutment member or the stop member away from each other, because these flat surfaces 47 and 50 lie substantially in a plane at rightangles to a line connecting the axis of the stud 29 with the axis of the stud 3l. These two surfaces offer then no resistance to the movement of the parts with respect to each lli) lili) other,other than the small rictional vresistance due to the tension ot the-spring 45 which holds these surfaces togethcin This friction is, however, so'small that there is substantially no appreciable wear thereon. lhen the sharp edge 51 slides beyond or clearsthe sharp corner`48 on the abutment, the spring 45 is free to act, and it immediately pulls the sharp corner 48 under the sharp edge or corner 51 ot the detent and turns the stop member 26 Vand the parts mounted thereon around its pivot 27. It is to bel notedthat'substantially the full contractive force of the spring 45 is operative to turn the stop member 2G, and the parts carried thereby, about the axis ot' the pivot pin 27. lt! therefore actsquickly, and snaps the member 26 into"stopping position in which the handle 30 bears against the stop pinA 53. In this `position the handle 30 is substantially held between the-two stops 53 and 52.` During this movement to stopping position, ythe stop `member also quickly swings the upwardly extending arm 23 o't theswitch 1() to the other end of the arcshaped'slot 24 in the base plate 8, and this movement of this arm`-23 swings the switch member (comprising the top plate 12, switch fingers 114-11; the bottom plate 13 and the insulatois 14 therebetween) around the axis ot' lthe pivot pin 15 and throws the lingers 11, 11 out ot engagement with the stationary contacts 19 and 20 with the result that the circuit through thel'eads or wires 21,22 i

is broken.

After such an operation of the device. the tone arm may be manually swung in the op posite direction, a new record may be put upon the machine, the arm 3G -may again be adjusted by the handle 39 on the arm 37 so that when the tono arm is in the last few convolutions of that sound recordl the pin 38 will re-engage the armBG, and the stopping mechanism is` then ready to be reset. To do this, the tone arm is again swung to the outside or the periphery of the record, and the handle 3() is manually grasped and swung in a clockwise direction.` During this movement the lever 30 and stop member 2G move as'one, until the sharp edge 5l of the detent 32 remfhesthe` sharp corner oredge 48 of the al'iutment.` The tension ot' the lcoiled spring 45 is such as to hold the under* side ofthe detent 32 against the arcshaped top surface 49 of the arm 46, and as the motion of the arm 30 is continued, the sharp corf ner or edge 48 will reach the sharp edge 51 of the detent: As soon as the sharp edges 48 and1 51 are clear of each other, the two flat surfaces 47 and 50 of the abutment member 28 and the detent`32 respectively will also be clear of each other, whereupon the spring 45 will draw the `detent down against the stop pin'34. Thismotion ot the arm 30 in a clockwise direction similarly moves the vber squarely against the stop pin` 523.

switch back toa position'wherei'n the switch lingers 11,y 1l `againwill engage the station automatically by the tone arm, when the dcvice is adjusted and set to stop the machine at the completion oit the `reproduction of `sound from a sound record on the turntable.

But it sometimes desirable to stop the reproduction of sound inthe middle of the record, before the pin 38 shallengage the' arm 36 at the completion of the reproduction of sound from the record, and this may be accomplished in this device by lightly touchingthe lever 30 by the finger ot'the operator to move it in an anticl'ockwise direction. By reason of the fact that the 'hat 'surfaces 4f? and 50 lie, as above referred to, substantially 1n a plane normal to a line connecting the axes or' the studs 29 and 31, this movement of the handle 30 in an anticlockwise direction is effected without substantial resistance' or wear betweeny the two surfaces,and when the abutment member or arm has been so turned with `respect to the stop member 26 that the-sharp corner or edge 48 reaches the sharp'edge or corner 51 of the detent,the spring 45 then becomes operative to draw the arm or projection 46 under the detent until `the spring 45 brings the `handle 30 carried bytheabutment mem- In this Way the manual application of a slight pressure `against the side of the handle 30 to move it in 1an anticlockwisei direction,

`causes av relative movement of the twolllat has =tinished using the machine Jr'or the purpose ot' reproducing sound. The sonndbox might be lifted so that the pin 38 would `not be operative toengage'the arm or- .finger 36 to release'the stop member 26101' a record might be taken off the machine while the turntable was rotating. with Lthe result that the motor would continue to run indefinitely,

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cam 8l slides under the stud 82 the link 74 forced downwardly against the tension ot' the spring 79 and the end of the pawlV 75 is freed from engagement with the teeth 72 of the ratchet wheel 71, whereupon' the spring 7 9'then turns the pawl 75 on its pivot pin 76 until the stop pin 7S engages the underside of the link 74. ln 4other words, when the end ot' the pawl 7 5 is thus thrown out of engagement with the ratchet teeth 7 2, the ratchet engaging end thereof is thrown rearwardly with respect to the direction of the mot-ion of the ratchet wheel 7l so that when the handle 30 is thrown in=a clockwise direction to reset the device and the link` 74 is `moved therewith to the leftback to the..position shown in Fig. l-the end of the pawl 75 will not re-engage the same .ratchet tooth that it did just prior to the time ywhen it was thrown out of engagement Wit-hi the ratchet by the cam 71 and stud 70, but it will engagesome ratchet tooth in the rear thereof.

Since the angular movement ot the ratchet is very slow, as above described, and since on substantially every movement of the stop member 26 tostoppingl position the pawl 75 is thrown outi of engagement with the ratchetV 7l and to such a position that .it will not 1re-engage the same tooth, but a tooth in the rear thereot,.it will be plain that this last described stopping ,mechanism will never operate to release the stop member 26.

unlessl the machine .continues to run for a. much longertime than is required to reproduce the sound from any record, and then only when the depending pin 38 has'failed to engage the arm or finger 36 or when the 1 machine has been lett ruiming with the sound box raised and the needle out of engagement with the talking. machinewrecord.

In Figs. 5 and G we have shown a modified tormJot device, )articularly adapted as a stop mechanism or talking machines f `which are driven by a spring motor, and i wherein the stop membercarries a brake pad which, upon the release ot the stop member is brought against the )er1 her roftfhe turntable to stop the further rotation ot the V.

talking machine motor, or against` some other part ot the operating mechanism.

ln this embodiment ot ourinvention, the hase plat\ 9 may be secured by suitable screws pa j tl'n'migh screw holes 9, i) Io the motor board il and they turntable Kl; with its periplieral flange 5 and 'friction surface. (i which carries the record 7, overlics and covers the stop mechanism, as in the first above described construction.

The stopI member 26 is pivoted upon a stationary pivot pin 27'rigi1dly secured to the base plate 8 `and the abutment member 2S is preferabl)v pivctedon a pivot pin4 29 rigidly secured to theisi'op member 26. The abutment member 28 is provided with a `handle 30 as in the previously described embodiment of our device. The detent 32 is mounted to oscillate slightly around the axis of the stud-31 rigidly secured to the base plate 8 between an `upper stop pin 33 struck upwardly trom the base plate 8 and a lower stop pin 34,shown in this form of our device as alsostruck up from the base plate 8.

The adjustable bifurcated arm 35 with its tinger 36 arranged to cooperate with the stud or pin 38 on the tone arm and'with the finger S37 provided with a handle 39 are all similar or the same as hasbeen shown and described `in connection with thev modifica.- tion shown in Figs. l and 2, but they frictional connection between the arm and the detent 32 is somewhat simplified. The' sleeve'flO ou the stud 3l is provided with a lower fiange 40a permanently secured thereto in any suitable manner, as by riveting, andserves toslightly space the hub on the adjustable arm v35 and the base plate 8. The sleeve 40 is also providedk on its upper end with a head or flange 40d between which and the detent is secured 4a spring washer 42', vthe action of which is to tightly hold the hub of the detent B2i. in frictional engagement with the hub of the adjustable arm 35. This construction is clearlyillustrated in Figs. 5 and 6.

The detent 32 is provided with an upwardlyextending rigid stud or pin't and the stop member 26 is provided With a rigid .stud or projection 44 to which the opposite ends of coiled spring 45 areattached `respectively.l The abut-ment memberf28 is provided with an arm or abutmenti having a tlat transverse surfacev I417, `a sharp edge. 4S and an upper arc-shaped surface 41), all` o1 whichis adapted to cooperate with the flat surface and sharp corner 5l on. the detent as above set forthinconnection with the first above described embodiment of 0in-invention'.

The stop .member 26 also n'o\f"ide l with a stop 52 with which the handle 30 engages when the latter is swung in a .clockwise direction to. set the mechanisni. The angular' moven'ient ot the stop member .26 about the axis ot its. pivot 27 is limited by stop pins 53' and 5.4 struck up 'from the base plate 8 and arranged in the path ot' nioven'ient ot the stop men'iber 26 in lieu ot the slop pins 5?. and 54. with which the 'li-.endle .3() engages to limit the movement lll') Except tor the fact that this device is operative to apply a brake to the turntable ot a talking machine, and the fact that the mechanism for moving the abutm-ent member when the motor has been inadvertently le't't ruiming is omitted, the device operates exactly as does the device lirst above described.

lVhen the depending pin 3S engages the linger 36 and slightly rocks or turns the adjustable arm 35 and with it the detent 32. the flat surface 5() slides, without substantial resistance, over the Hat surface 47 until the sharp edge or corner 5l of the detent clears the sharp corner 48 ot the abut mont member, and then the spring 45 turns the stop member 26 about the pivot pin 2T to bring the brake pad S4 against the `flange 5 of the turntable. lVhen for any reason duringvthe reproduction of sound from a record, and belore the depending stud 38 engages the arm 36, it is desirable to stop the motor, the handle 30 may be manually pressed in an anti-cloclwise direction to move the flat surface 47 of the abritment over the fiat surface 50 of the detent until the sharp corner edge 48 clears the sharp corner 5l of the detent, whereupon the spring 45 comes into operation and swings the stop member 26 to the position wherein the brake pad S4 engages the flange 5.

The resetting of the device is accomplished bv moving the handle 30y in a clockwise direction. The handle 30 by reason. of its engagement with the stop 52, turns the stop member 26 and the abutment member 28 together as one, around the axis of the pin L?? in a clockwise direction. the curved sur'- "'.fe 49 ot the abutment sliding` under the end ot the detent until the sharp corner .4:8 clears the sharp edge 5l on the detent whereupon the spring 45 turns the detent 3:2 on the axis o't the stud 3l and brings it against the lower stop pin 34 carried by the plate, the fiat surface -lT of the abutment and the tlat sui-'tace 50 o'tv the detent lfeing clear ot each other. The release at this time ot the handle 30 leaves the coiled spring 45 tree to bringsaid flat surfaces 47 and fl into engagement with each other. This operation is exactly like that ot the device first above described. In thus bringiuu' the op member .26 into this non-stop'- giiiug posiiiim. the brake pad 8dmoved out oi' engagement with the flange 5 on the turntable i. and is held in the position shown in File'. t until released either by the movement of the biiiurcated arm 35, or the anti-clockwise manual movement of the handle 30,

In both ot the forms or embodiments of our invention, as above disclosed and described, the abutment member is a movable one, preferably pivoted to the stop member in such a way as to permit ot its movement relative to the stop member, but it is to be understood that the construction and arrangement of these parts may be varied considerably without departing from the spirit and scope ot our invention.

It will also be clear that we have provided a mechanism wherein the disengagement ot the abutment member with the detent, when the mechanism is in non-stopping position, may be ellectcd in three ways to stop a talking machine; (l) by the engagement ot a projection on the tone arm with the adjustable member frictionally connected to the detent to automatically move the detent out of engagement with the abutment, to allow the spring to throw the stop member from non-stopping to stopping position; (2) by the manual movement oit the handle to move the abutment out of engagement with the end ot the detent, so that the. spring may throw the stop member from non-stopping to stopping position; and (3) by a time stop mechanism operative to auton'iatically move the abutment out ot engagement with the end ot the detent, to allow the spring to throw the stop member trom non-stopping to stopping position. It will be observed that in these three ways of actuating the stopping mechanism, the detent and the abutment` by the engagement oit which the stop member is maintained in non-stopping position, are held together and are so moved with respect to each other that there is substantially no wear between the coacting parts, with the result that after long and continued use the device may be re-set as accurately as when it was operated for the iii-st time. The construction is such, how ever, that it there were a wear on the co acting surtaccs ot the abutment and detent, that wear would not substantially change the length ot the fiat co-operating surfaces and would therefore not vary the time within which the end oit the detent is in e11- gagement with the end oit the abutment, alter the detent begins to move and up to the point when the sharp edge of the detent reaches the sharp corner ot the abutment, and therefore a substantial wear ot' the said 'llat surfaces would not a tlfect the accuracy with which the device could be set to operate.

Our eonstructhm is such that ihcrc is no jamming ot Ibe parts with respect to cach other to release the stop member, because the movement between the detent and abutment is merely a sliding movement ot one liat surface against the other, without any tendency to move the stop member during such sliding movement, and because the Yt'riction between the detent and abutment is only that produced by the comparative light pressure with which the coil spring presses. the small liat surface of the abutment against the small flat surface of the detent.

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There is substantially no resistance lto be overcome in sliding the detent out of en gagen'ient with the abutment, or in sliding the abutment out ot engagement with the detent except that due to the slight friction betweenthe said flat surit'ace on the detent and the coacting tlat surface on the abutment.

In the above construction the length of time required for the tripping or releasing action to be )ertormed, atter the detent or the abutment has once begun to move automatically, the one with respect to the other, will depend a great deal on the distance that one ot' said members is required to move or slide over the ilat surface of the other. Since the movement oi the tone arm and of the 'ratchet Ais relatively slow, the extent to which said flat surfaces overlap and are in actual contact with each other when the device is set in non-stopping position is preferably made very small, so that one member may move out of engagement with the other member in the time required tor a stylus to traverse two or three convolutions ot' a record groove. By thus making the extent to which the flat surfaces on said members overlap, relatively small and by providing a construction wherein the. wear on those surfaces is negligible, the device may be very accurately and delicately adjusted to aetuate the stop device at an exact predetermined or selected point in the record groove.

. Having thus described our invention, what we cla-im and desire to protect by Letters Patent is:

l. In a stop mechanism the combination of a stop member movable into stopping and into non-stopping positions, an abutment member mounted on said stop member and movable with respect thereto, a detent tor lmlding said stop member in non-stopping position, yielding means tending to move said stop member into stopping position and holding said abutment against said detent when said stop member is in non-stopping position, and means to more said abutment member with respect to said detent out ol' engagement with said detent to release said stop member. whereby said yielding means moves said stop .neu'iber into sioliping po i ion.

2. In a stop mechanism the combination of, a stop member movable into stopjg'iing and into non-stopping poi ions. au abut.- ment member mounted on said stop member and movable with respect thereto, a detent 'tor holding said stop member in non-stopping position, yielding means tending to move said member into stopping position and holding said abutment. member against said detent when said stop member is in non-stopping position, and means to move said abutment member with ref-speci to said detent and with respect to said stop inem ber to release said stop member, wherebyv said yielding means moves said stop member into stopping position.

Inr a stop mechanism the combination oit a stop member movable into stopping and non-stopping positions, an abutment member mounted on and movable with respect to said stop member, a detent for holding said stop member in non-stopping position, yieiding means tending to move said stop member into stopping position and holding said abutment member against said detent when saidstop member is in non-stopping position, and means to automatically move said abutment member with respect to said stop member and said detent to disengage said detent and said abutment member. i

4. In a stop mechanism the combii'iation ot a stop member movable into stopping and non-stopping positions, a pivoted member mounted on said-stop member, a detent -for holding' said stop member in non-stopping position, yielding means tending to move said stop member into stopping position and holding said pivoted member against said detent whim said ystop member is in nonstopping position, and means to automatically move said pivoted member to disengage said pivoted member and said det-ent to release said stop member, whereby said yielding means throws said stop member to stopping position. i

5. In a stop mechanism the conibination of a stop member movable into stopping and into non-stopping positions, a movable member mounted on said stop member and having an abut-ment, a detent tor retaining id vstop member in non-stopping position, yiel ding means tending to move said stop menr v ber into stopping position and holding said abutment against said detent when said stop member is in non-stopping position, and means independent of said detent to automatically move said movable member with respect to said detent to disengage said abutment from said detent.

('3. In a stop mechanism. the combination of a Vstop member movable into stopping and into non-stoliping positions, -yielding means tending to hold said member in stopping posit-imi. a detest, an abutment inembor mounted ou said stop niieinbef.' and movable with respect thereto and having a projeetion arranged to be held against said de tent by said yielding means to retain said stop member in noirstmiping position, and means to manually move said abutment member to disengage said projection Afrom said detent,

7. In a stopping mecl'ianism the combination oi a4 stop member movable into stopping and non-stopping positions, an abut ment member carried by -xd stop member and mo" ible with respect thereto, a detrnt lill) tor holding said stop member in non-stopping position, yielding means tending to move said stop member into stopping position and holding said abutment member against said detent when said stop member is in non-stopping position, automatic means to disengage said detent and said abutment, .whereby said yielding means automatically moves said stop member into stopping position, and means carried by said abutment member by the manual movement of which in one direction said stop member is released from said detent and in the other direction said stop member is moved into non-stopping position and said abutment member is brought into reengagement with said detent.

8. In a stop mechanism, the combination of a stop member movable into stopping and into non-stopping positions, a spring tending to hold said member in stopping position, a pivoted detent, a pivoted member mounted on said stop member and having an arm extending outwardly away from the axis of said pivoted member and generally toward the pivot of said detent, the end of said arm being arranged to be held by said spring against the end of said detent to hold said stop member set in non-stopping position, the engaging surfaces of said arm and detent being fiat and disposed substantially in a plane disposed at right angles to a line connecting the pivotal axes of said arm and detent, and means to disengage said detent and said arm whereby said spring. moves said stop member into stopping position.

9. In a stop mechanism, the combination of a stop member movable into stopping and into non-stopping positions, a spring tending to hold said member in stopping position, a pivoted detent, a pivoted member having an arm extending outwardly away from the axis of the pivot of said pivoted member and generally toward the pivot of said detent, the end of said arm being arranged to be held by said spring against the end of said detent to hold said stopping member set in non-stopping position, means to automatically move said detent out of engagement with said arm to release said stop member, and means to automatically move said arm out of engagement with said detent to release said stop member.

10. In a stop mechanism, the combination of a stop member movable into stopping and into non-stopping positions, a spring tending to hold said member in stopping position, a pivoted detent, a pivoted member having an arm extending outwardly away from the axis of the pivot of said pivoted member and generally toward the pivot of said detent, the end of said arm being arranged to be held by said spring against the end of said detent to hold said stopping member set in non-stopping position, means to automatically move said detent out of engagement with said arm to release said stop member, and means to manually move said arm with respect to said stop member and out of engagement with said detent to release said stop member.

11. In a stop mechanism, the combination of a stop member movable into stopping and into non-stopping positions, a spring tending to hold said member in stopping position, a detent, a pivoted member mounted ou said stop member and providing an abutment arranged to be held against said detent by said spring to hold said stop member in non-stopping position, and manually operable means connected to said pivoted member and movable in one direction to move said abutment out of engagement with said detent to release said stop member, and movable in the other direction to move said stop member into non-stopping position and said abutment into holding engagement with said detent.

12. In a stop mechanism, the combination of a spring, a stop member movable into stopping and into non-stopping positions and normally held in stopping position by said spring, a movable member mounted on said stop member and providing an abutment, a detent against which said abutment is held by said spring when said stop member is in non-stopping position, means to automatically disengage said detent and said abutment to release said stop member whereby said spring moves said stop member to stopping position, and manual means movable in one direction to disengage said detent and said abutment to release said stop member and in the opposite direction to move said stop member into non-stopping position and said abutment into engagement with said detent. Y

13. In a stop mechanism, the combination oi a stop member movable into stopping and into non-stopping positions, a springtending to move said member into stopping position, a detent, and a manually operable member mounted on said stop member to be moved relatively thereto and providing an abutment arranged to engage said detent when said stop member is in non-stopping position, the movement of said manually movable member in one direction being operative to disengage said abutment from 'aid detent to release said stop member and in the opposite direction to move said stop member into non-stopping position and Said abutment into holding relation with respect to said detent.

14. In a stop mechanism, the combination of a stop member movable into stopping and into non-stopping positions, a spring tending to move said member into stopping position, a detent, a member movable with respect to and permanently mounted on said stop member and providing an abutment for engagement With said detent when said stop member is in non-stopping position, automatic means to move said detent out of engagement With said abutment to release said stop member, automatic means to move said movable member with respect to said stop member and said abutment out of engagement with said detent to release said stop member, and manual means to move said movable member with respect to said stop member to disengage said abutment from said detent to release said stop member.

15. In a stop mechanism, the combination of a stop member movable into stopping and into non-stopping positions, a spring tending vto move said member into stopping position, a detent, a member permanently mounted on said stop member and movable With respect to and providing an abutment `for-'engagement With said detent to retain said stop member in non-stopping position, automatic means to move said detent out of engagement with said abutment to release saidI stop member, automatic means to move said movable member with respect to said stop member and said abutment out of engagement with said detent to release said stop member, and means manually movable in one direction to move said movable member with respect to said stop member and said rabutment out of engagement with said detent kto release said stop member and in the opposite direction to move said stop member into non-stopping position and said abutmentinto engagement with said detent.

16. In a stop mechanism, the combination of a stop member, movable into stopping and into non-stopping positions, a spring tending to hold said member in stopping position, a detent, said stop member being provided with an abutment adapted to be held against said detent by said spring to hold said stop member in non-stopping position,` and means to slide said abutment transversely vover and out of engagement With said detent to release said stop member and render said spring operative to Y abutment engage being substantially flat and disposed in a plane .normal to a line drawn from said surfaceto the pivot'of: said detent, and means to slide the engaging surface of said abutment-substantially in the plane of said surface, means to slide the detent engagingportion of said abutment in the plane of said surface over and out of engagement With said detent to release said stop member from non-stopping position.

18. In a stop mechanism, thecombination of a stop member movable into stopping and non-stopping positions, a detent, an abutment on said stop member having end-to-end engagement with said detent to retain said stop member in non-stop ing f position, means tending to move sai stop member into stopping position, and meansto disengage said abutment and said detent by transverse movement of either vrelative to the other. i

19. In a stop mechanism, the combination of a stop member movable into stopping and nonsstopping positions, an abutment `there` on, a detent having cuddle-end engagement with said abutment toretain saidstop member in non-stopping position, means tending to move said stop member intostopping position, and means to disengage said detent and said abutment by transverse movement of either relative to the other. In Witness whereof, we have hereunto se our hands this 25th day of August, A. D. 1922. FREDERIC S. CALDERWOOD.

RUDOLPH E. ZERUNEITH. 

